Bernard Thébaud works at the Ottawa Hospital Research Institute (OHRI) and Children’s Hospital of Eastern Ontario (CHEO), and is also a member of the Ottawa Stem Cell Initiative. Dr. Thébaud has proposed a new therapy that utilizes umbilical cord stem cells to treat a lung disease called bronchopulmonary dysplasia (BPD), which was previously thought to be untreatable.
Thébaud described BPD in this way: “BPD is a lung disease described 45 years ago in which we have made zero progress. And now, with these cord-derived stem cells there is a true potential for a major breakthrough. I am confident that we have the talent and the tools here at CHEO and OHRI to find a treatment for BPD. These findings published today are helping us get there.”
Every year, BPD affects ~10,000 premature newborns in Canada and the US. The lungs of infants with BPD are not developed enough to function properly, and consequently the baby has to be placed on a ventilator in order to receive sufficient quantities of oxygen. Mechanical respirators, however, are very hard on such young, friable lungs, and the lungs then to fray and this prevents them from developing properly. The longer the baby stays in the neonatal intensive care unit, the greater the degree of multiorgan damage (retina, kidneys, and the brain). Therefore, the baby needs oxygen to survive, but the very act of giving them oxygen eventually hastens their death.
Thébaud’s research team used new-born rats that were given oxygen soon after their premature birth. Some were given stem cell treatments and others were not. These experiments produced five new findings:
1) Mesenchymal stem cells (MSCs) from human umbilical cord can protect the lungs when injected into the lungs as the animals were put on oxygen.
2) MSCs had a tendency to stimulate repair of the damaged lungs when injected two weeks after the animals were put on oxygen.
3) The medium in which the MSCs were grown (conditioned medium) was injected into the lungs instead of the cells, this medium had the same reparative and protective effects as the cells themselves. This suggests that it is the cocktail of growth factors and other supportive molecules secreted by the MSCs that provide their healing properties. Such a mechanism, in which the cells secrete molecules that affect nearby cells and tissue, is known as a “paracrine” mechanism.
4) When examined six months after treatment (the equivalent of 40 human years), the treated animals had better exercise performance and more normal lung structure.
5) MSC administration did not adversely affect the long-term health of the laboratory animals. None of the MSC-treated animals had any tumors and MSCs given to control animals that did not have BPD were also normal six months later.
Thébaud would like to conduct a pilot clinical (Phase I) study within two years with around 20 human patients in order to determine if this treatment is feasible and safe. If the treatment turns out to be safe, Thébaud would like to initiate a randomized controlled (Phase II) clinical trial.
See Maria Pierro et al., “Short-term, long-term and paracrine effect of human umbilical cord-derived stem cells in lung injury prevention and repair in experimental bronchopulmonary dysplasia,” Thorax 2012: DOI:10.1136/thoraxjnl-2012-202323.